A conventional electric transmission tower is a truss shaped steel structure constructed from the ground to a height of several tens of meters and is configured with a heavy material having a dead load in a range of several tens of tons to several hundreds of tons in order to construct electric transmission lines. Such an electric transmission tower typically has four main pole members which are disposed in square, and a lower end of each of the four main pole members is fixed to the ground by means of a concrete base body.
To construct electric transmission tower, a method of first excavating the ground and deposing a concrete surface in the excavated ground at a level, constructing and disposing four foundation concrete structures in square, and sequentially assembling the four foundation concrete structures in a truss type having angles up to a predetermined height is used to complete installation of an electric transmission tower.
A base body for supporting an electric transmission tower is generally manufactured at a construction site so that a large amount of material and equipment and a wide workspace are required. However, since a location at which an electric transmission tower is installed is a ridge of mountain, a steeply sloped land, or the like, there are problems in that transportation of materials and equipment is very difficult, environmental damage occurs due to a large scale foundation construction, and a long construction period is required.